>I was getting it at 1024*768 with strings as short as 40 characters.

Haven't tried that, but I believe you, since I saw it too. :)

>yes, I take the point, but I am also providing the option for the user to turn off the tooltips once they have familiarised themselves sufficiently with the functions of the various fields, at which point it will then revert to right click...

In that case, that sounds like good GUI...I have "introductory help" (but using small floating form) in an app, too...